121355243545 has 16 divisors (see below), whose sum is σ = 147647646720. Its totient is φ = 95743701504.

The previous prime is 121355243543. The next prime is 121355243557. The reversal of 121355243545 is 545342553121.

It is a cyclic number.

It is not a de Polignac number, because 121355243545 - 2¹ = 121355243543 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121355243498 and 121355243507.

It is not an unprimeable number, because it can be changed into a prime (121355243543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 304825 + ... + 579334.

It is an arithmetic number, because the mean of its divisors is an integer number (9227977920).

Almost surely, 2^121355243545 is an apocalyptic number.

It is an amenable number.

121355243545 is a deficient number, since it is larger than the sum of its proper divisors (26292403175).

121355243545 is an equidigital number, since it uses as much as digits as its factorization.

121355243545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 884544.

The product of its digits is 360000, while the sum is 40.

Adding to 121355243545 its reverse (545342553121), we get a palindrome (666697796666).

The spelling of 121355243545 in words is "one hundred twenty-one billion, three hundred fifty-five million, two hundred forty-three thousand, five hundred forty-five".